First make sure you file a report with eBay so that they will release the sellers personal info to you, address he used for eBay, his e-mail address, and phonenumber.
Then report the seller for mail/internet fraud to ic3.gov, your local post office, and the sellers local police station.
As far as PayPal goes you've got three options.
1. If you got lucky and the seller did not use tracking or delivery confirmation just file a claim that you never got the item.
2. If your payment was funded by a credit card, then just call up your credit card company.
3. Seller has a tracking #, you are going to need to file a claim, paypal will ask you to take the shoes to a non-biased third party expert (any nike store)and have a manager sign a letter stating they are fake. Send that to paypal, wait a couple weeks for them to decide. Then hope the seller still has money ishis paypal account. If he doesn't the sellers account will become negative (un-usable) until he pays them back, usually they never pay back so you win theclaim, they lose their paypal account. but you never get your money back.
If all fails:
Post the guys info on NikeTalk and see if any members lives in his area and are willing to help you out.
